Hi Timo,
first of all thanks a lot for your reply. I tried your advise and got exactly what I wanted. It is a bit of a shame that it isn´t an absolutly easy and fast way, but it works. I don´t know how affinity knows what "a" and what "b" is in the equation, but it works. Is there a part in the manual to get a bit more into this? I had a bit of a problem to get the two neccessary layers in the right position, because they need to be at the same level AND be seperated, not sure why. The managemant with the layers is a bit different than in Ps, so I am not that much into it yet. I have to find some tutorials to understand that better.
I added a red fill-layer under the others and so it is possible to change the oppacity of the masked regions to hide them a bit and there is also an option to mark them red (or any other color) with a defined oppacity. So there is even more options than in Ps now. Although I need much more layers and at least one, better two groups.
It would be a goalchanger if Affinity will get these option in a further version for every masked created with a simple click. I am not sure why it isn´t part of the software at the moment, because for me it is very hard to mask without this feature.
I tried to put this into an "action" (macro), but it seems that there is no possibility to change the order of layers in macros, is it? It would be great to have the option to create the layers by just one click or shortcut.
Also I tried to use the layer-effect functions (color overlay) to solve the problem. It works with some masks, but it seems that it will not work with everyone. I am not sure when exectly this is an option. Maybe this is an other solution.
Thanks again
Daniel